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  • First Simultaneous Lidar Observations of Thermosphere‐Ionosphere Sporadic Ni and Na (TISNi and TISNa) Layers (∼105–120 km) Over Beijing (40.42°N, 116.02°E)
Title: First Simultaneous Lidar Observations of Thermosphere‐Ionosphere Sporadic Ni and Na (TISNi and TISNa) Layers (∼105–120 km) Over Beijing (40.42°N, 116.02°E)
Abstract We report the first simultaneous lidar observations of thermosphere‐ionosphere sporadic nickel and Na (TISNi and TISNa) layers in altitudes ∼105–120 km over Yanqing (40.42°N, 116.02°E), Beijing. From two years of data spanning April 2019 to April 2020 and July 2020 to June 2021, TISNi layers in May and June possess high densities with a maximum of 818 cm−3on 17 May 2021, exceeding the density of main layer peak (∼85 km) by ∼4 times. They correlate with strong sporadic E layers observed nearby. TISNa layers occur at similar altitudes as TISNi with spatial‐temporal correlation coefficients of ∼1. The enrichment of Ni in TISNi is evident as the [TISNi]/[TISNa] column abundance ratios are ∼1, about 10 times the main layer [Ni]/[Na] ratios. These results are largely explained by neutralization of converged Ni+and Na+ions via recombination with electrons. Calculations show direct recombination dominating over dissociative recombination above ∼105 km.  more » « less
Award ID(s):
2110428
PAR ID:
10372007
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
49
Issue:
16
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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